A U.S. congressman traveling in Russia said Russian intelligence officials told him the Boston Marathon bombing could have been prevented if their American counterparts, the FBI and CIA, had acted on their warnings in 2011 - that Tamerlan Tsarnaev was planning on traveling abroad to join an underground Islamic terrorist group.

U.S. officials have said that the information the Russians shared was vague, but Congressman Bill Keating, Democrat of Massachusetts, tells CNN he was shown detailed intelligence by the Russian FSB, successor to the KGB.

Those details include names, cell phone numbers, addresses, and social media indicating that Tsarnaev had originally planned to get involved with Palestinian insurgents. That plan fell through when he had trouble leaning Arabic, as Keating first told The Boston Globe.

Friday morning, new video surfaced of the Tsarnaev brothers working out in a Boston area gym, just before allegedly committing the terrorist attack on the Boston Marathon. The video, seen below, shows the two brothers working up a sweat, casually jumping rope, and shadow boxing.

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